Error while performing a subscription re-sync: Failed to execute SQL query: Login failed for user 'sa'

Symptoms

• An unfinished migration session is active on the destination server
• A password for the MS SQL sa user was changed on the source server after the example.com subscription have been transferred
• Trying to perform a re-sync of the example.com subscription's database fails with the following error:
  

  PLESK_ERROR: Attempt #1 failed with the following error:
  Failed to execute SQL query: Login failed for user 'sa'. DB-Lib error message 18456, severity 14:
  General SQL Server error: Check messages from the SQL Server
  DB-Lib error message 20002, severity 9:
  Adaptive Server connection failed
  
  

  WARNING: The issue persists after updating the 'sa' user password both on the source and destination server once again

Cause

An old password for the sa user is still cached on the source server

Resolution

• Re-sync business objects
• Re-sync external IDs

4. After the business object re-sync has finished, proceed with re-syncing the example.com subscription's database